I'm a lightweight; always have been. I didn't get properly drunk until I was 25, on a night out which culminated in a spectacular public vomiting in a Chinese restaurant. Ever wondered what the clatter of 60 pairs of chopsticks being simultaneously dropped in disgust might sound like? Don't ask me. I can't remember. I was too busy bitterly coughing what remained of my guts all over the carpet.

Not a big drinker, then. Like virtually every other member of my generation, I smoked dope throughout my early 20s. It prevented me from getting bored, but also prevented me from achieving much. When you're content to blow an entire fortnight basking on your sofa like a woozy sea lion, playing Super Bomberman, eating Minstrels and sniggering at Alastair Stewart's bombastic voiceover on Police Camera Action! there's not much impetus to push yourself. Marijuana detaches you from the world, like a big pause button. The moment I stopped smoking it I started actually getting stuff done. I still sit on my sofa playing videogames, necking sweets and laughing at the telly, but these days if I have to leave my cocoon and pop to the corner shop to buy a pint of milk before they close, it's a minor inconvenience rather than a protracted mission to Mars. That was the worst thing about being stoned: there came an inevitable point every evening where you'd find yourself shuffling around a massively overlit local convenience store feeling alien and jittery. Brrr. No thanks.

I tried other things, only to discover they weren't for me. LSD, for instance, definitely isn't my bag. Call me traditional, but if I glance at a wall and before my very eyes it suddenly starts smearing and sliding around like oil on water, my initial reaction is not to be amused or amazed, but alarmed about the structural integrity of the building. My most benign lysergic experience consisted of an hour-long stroll around an incredibly verdant, sun-drenched meadow, watching the names of famous sportsmen appear before me in gigantic 3D letters carved from fiery gold. Eventually someone passed me a cup of tea and the spell was broken: there I was, sitting in a student halls of residence, watching late-night golf on BBC2 on a tiny black-and-white TV. From that point on it was like being trapped in a David Lynch film that lasted for eight hours and was set in Streatham. Once again: Brrr. No thanks.

These days I'm sickeningly lily-livered, by choice rather than necessity. I don't smoke, I drink only occasionally, and I'd sooner saw my own feet off than touch anything harder than a double espresso. I don't want to get out of my head: that's where I live.

In summary: if I've learned anything, it's that I don't much care for mood-altering substances. But I'm not afraid of them either. With one exception.

It's perhaps the biggest threat to the nation's mental wellbeing, yet it's freely available on every street – for pennies. The dealers claim it expands the mind and bolsters the intellect: users experience an initial rush of emotion (often euphoria or rage), followed by what they believe is a state of enhanced awareness. Tragically this "awareness" is a delusion. As they grow increasingly detached from reality, heavy users often exhibit impaired decision-making abilities, becoming paranoid, agitated and quick to anger. In extreme cases they've even been known to form mobs and attack people. Technically it's called "a newspaper", although it's better known by one of its many "street names", such as "The Currant Bun" or "The Mail" or "The Grauniad" (see me – Ed).

In its purest form, a newspaper consists of a collection of facts which, in controlled circumstances, can actively improve knowledge. Unfortunately, facts are expensive, so to save costs and drive up sales, unscrupulous dealers often "cut" the basic contents with cheaper material, such as wild opinion, bullshit, empty hysteria, reheated press releases, advertorial padding and photographs of Lady Gaga with her bum hanging out. The hapless user has little or no concept of the toxicity of the end product: they digest the contents in good faith, only to pay the price later when they find themselves raging incoherently in pubs, or – increasingly – on internet messageboards.

Tragically, widespread newspaper abuse has become so endemic, it has crippled the country's ability to conduct a sensible debate about the "war on drugs". The current screaming festival over "meow meow" or "M-Cat" or whatever else the actual users aren't calling it, is a textbook example. I have no idea how dangerous it is, but there seems to be a glaring lack of correlation between the threat it reportedly poses and the huge number of schoolkids reportedly taking it. Something doesn't add up. But in lieu of explanation, we're treated to an hysterical, obfuscating advertising campaign for a substance that will presumably – thanks to the furore – soon only be available via illegal, unregulated, more dangerous, means. If I was 15 years old, I wouldn't be typing this right now. I'd be trying to buy "plant food" on the internet. And this time next year I'd be buying it in a pub toilet, cut with worming pills and costing four times as much.

Personally speaking, the worst substances I've ever encountered are nicotine (a senselessly addictive poison) and alcohol (which spins the inner wheel of judgment into an unreadable blur). Apart from the odd fond memory, the only good thing either really have going for them is their legality. If either had been outlawed I'd probably have drunk myself blind on cheap illegal moonshine or knifed you and your family in the eye to fund my cigarette habit.

But then I'm pretty ignorant when it comes to narcotics. Like I said, I'm a lightweight. I can absolutely guarantee my experience of drugs is far more limited than that of the average journalist: immeasurably so once you factor in alcohol. So presumably they know what they're talking about. It's hard to shake the notion half the users aren't trying to "escape the boredom of their lives": just praying for a brief holiday from society's unrelenting bullshit.